cve/2017/CVE-2017-12190.md

### [CVE-2017-12190](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-12190)
![](https://img.shields.io/static/v1?label=Product&message=Linux%20kernel%20through%20v4.14-rc5&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=%3D%20Linux%20kernel%20through%20v4.14-rc5%20&color=brighgreen)
![](https://img.shields.io/static/v1?label=Vulnerability&message=CWE-400&color=brighgreen)

### Description

The bio_map_user_iov and bio_unmap_user functions in block/bio.c in the Linux kernel before 4.13.8 do unbalanced refcounting when a SCSI I/O vector has small consecutive buffers belonging to the same page. The bio_add_pc_page function merges them into one, but the page reference is never dropped. This causes a memory leak and possible system lockup (exploitable against the host OS by a guest OS user, if a SCSI disk is passed through to a virtual machine) due to an out-of-memory condition.

### POC

#### Reference
- https://usn.ubuntu.com/3582-1/
- https://usn.ubuntu.com/3583-2/

#### Github
No PoCs found on GitHub currently.